Viola Cornuta King Henry is indeed royal with its rich, dark purple shades, golden eye and whisker markings. These purple Violas look stunning in your containers and window. Viola seeds are rewarding to grow and the plants are hardy and tolerant of most soils. Sow the flower seeds indoors in late winter or outdoors early spring or late summer. Flowers are edible and are often used in salads, candied on specialized cookies and food decoration on spectacular cakes and cheese plates. Perennial, zone 6-9.